Diphenylnaphthylmethane dye.



. T all who? it may concern:

'ceed as follows, the parts being by weight: A

UNITED STATES PATENT OFFICE;

MAX WETLER, OF ELBERFELD, GERMAN Y, ASSIGNOR TO FARBENFABRIKEN VORM.FRIEDR.

BAYER & 00., OF ELBERFEL'D; GERMANY, A CORPORATION OF GERMANY.

DIPHENYLNAPHTHYLMETIIANE DYE.

Application filed March 13,

Be it known that I, MAX Wmmm, doctor of philosophy, chemist, a cltlzenof the German Empire, residing at Elberl'eld, Germany useful Imrovements in Diphenvlnap]ithylmethane yes, of. which the following is aspecification.

My invention relates to the manufacture and production of new dyestuffsof the diphenylnaphthylmethanc series which are obtained by condensingtetraalkylized diamiobcnzhydrols with 1-naphthol-3.S-disulfonic acid andoxidizing the leuco-compounds thus obtained. The new dyestuffs are darkpowders soluble in water with a bluish color. They dye wool from acidbaths from blue to green shades which are remarkable for their excellentfastness to alkalies.

In carrying out my invention I can promixture of 105 parts oftetramethyl=paradiaminob'enzhydrol, 149 parts ofl-naphthol-3.8-disulfonate of sodium and 1200 warts of sulfuric acid (40per cent.) is heated ior about 60 hours on the water bath until thewhole hydrol has entered into reaction. The leuco-com ound which hasalmost entirely separatorv out is then completely precipitatm by theadditionof an equal volume of water. To produce""the coloring matterfrom this leuco-compound, 40 parts of it are dissolved in 340 parts ofwater and 8.4 parts of sodium carbonate and then at a temperature ofabout 65 0;, 180 parts of a lead dioxid paste (containing 10 per cent.of PbO are added, the solution being well stirred and the stirring isafterwards continued for a quarter of an hour. When the oxidation isfinished the lead is precipitated by means of sodium carbonate and thenew dyestufl' is Specification of Letters Patent.

precipitated in the usual manner by the addi- Patented June so, 1908.

1908. Serial No. 420,806.

tion of sulfuric acid and common salt; It is after being dried andpulverized in the shape of its acid sodium salt a dark redowder solublewith difficulty in water with a bluishgreen color and soluble inconcentrated sulfuric acid with a yellow color. It dyes wool from acidbaths greenish-blue shades. The dye from tetracthylhydrol dyes woolbluishreen.

h Having now described my invention and in what manner the same is to beperformed, I declare that what I claim is:

l. The herein-described newdyestuffs of the (liphenylnaphthylmethaneseries obtainable by condensing tctraalkylized diaminobcnzhydrols with1-naphthol-3.8-disulfonic acid and oxidizing the leuco-compounds thusobtained, which dyestuffs are after being dried and pulverized darkpowders soluble in water with a bluish color and dyeing wool from acidbaths from blue to green shades, substantially as described.

2. The herein-described new dyestuff of the iliphenylnaphthylmethaneseries obtainable by condensing tetramethylara-diaminobenzhydrol withl-naphtho -3.8-disulfonic acid and oxidizin the leuco-com ound thusobtained, which yestuf'f is after being dried and pulverized in theshape of its acid sodium salt a dark red owder soluble with difficultyin water wit a bluish-green color, soluble in concentrated sulfuric acidwith a yellow color, and dyeing wool from acid baths greenish-blueshades, substantially as described.

In testimony whereof I have hereunto set my hand in the presence of twosubscribing witnesses.

' MAX WEILER. Witnesses:

O'r'ro Konio, WM. WASHINGTON BRUNSWICK.

